April 27, 2006
01:00 PM (EDT)

News Release Number: STScI-2006-18

Hubble Provides Spectacular Detail of a Comet's Breakup

April 27, 2006: Hubble Space Telescope is providing astronomers with extraordinary
views of Comet 73P/Schwassmann-Wachmann 3. The fragile comet is
rapidly disintegrating as it approaches the Sun. Hubble images
have uncovered many more fragments than have been reported by
ground-based observers. These observations provide an unprecedented
opportunity to study the demise of a comet nucleus. The comet is
currently a chain of over three dozen separate fragments, named
alphabetically, stretching across the sky by several times the
angular diameter of the Moon. Hubble caught two of the fragments
(B and G) shortly after large outbursts in activity. Hubble shows
several dozen "mini-comets” trailing behind each main fragment,
probably associated with the ejection of house-sized chunks of
surface material. Deep-freeze relics of the early solar system,
cometary nuclei are porous and fragile mixes of dust and ices that
can break apart due to the thermal, gravitational, and dynamical
stresses of approaching the Sun. Whether any of the many fragments
survive the trip around the Sun remains to be seen in the weeks ahead.